RNF43 and ZNRF3: Versatile regulators at the membrane and their role in cancer

Area of Science:

• Molecular Biology
• Oncology
• Cell Signaling

Background:

• RNF43 and ZNRF3 are key negative regulators of Wnt/β-catenin signaling.
• They maintain Wnt-receptor homeostasis, preventing pathway overactivation.
• Mutations in RNF43 and ZNRF3 are implicated in various cancers, especially gastrointestinal tumors.

Purpose of the Study:

• To explore the broader roles of RNF43 and ZNRF3 beyond Wnt signaling.
• To detail the regulatory mechanisms of RNF43 and ZNRF3 activity, including phosphorylation and ubiquitination.
• To analyze cancer-associated mutations in RNF43 and ZNRF3 and their impact on tumor growth.

Main Methods:

• Literature review and analysis of existing research on RNF43 and ZNRF3.
• Examination of mutation data in cancer genomes.
• Discussion of post-translational modifications affecting protein function.

Main Results:

• RNF43/ZNRF3 also regulate other tumor-associated proteins like EGFR, BRAF, and the BMP signaling pathway.
• Phosphorylation and ubiquitination critically fine-tune RNF43 and ZNRF3 activity.
• Cancer mutations in RNF43/ZNRF3 promote tumor growth through various mechanisms.

Conclusions:

• RNF43 and ZNRF3 play multifaceted roles in cancer biology, extending beyond canonical Wnt signaling.
• Understanding their regulation and mutation landscape is crucial for developing targeted cancer therapies.
• The study challenges the notion of dominant-negative activity for certain RNF43/ZNRF3 missense mutations.